IBM AT power supply case/cooling question

I'd suggest you consider an AC fan with a series capacitor in one side or the other of the supply to the fan. If you're ambitious, you can do quite a little with that sort of hookup, trading off fan noise for effective cooling power. If you put about 0.47uF in series with a typical small AC fan, it will cut the torque considerably, and that will cut the amount of air it moves. If you put a normally-open SSR, controlled by a temperature sensor in some critical area of your enclosure, in parallel with the cap, then have the control enable the SSR whenever the temp is above a certain point, it will speed up the fan and keep running at high speed until the control signal goes away. You then play with the hysteresis until you get satisfactory performance. Dick ----- Original Message ----- From: <philip(a)awale.qc.ca> To: <classiccmp(a)classiccmp.org> Sent: Tuesday, April 30, 2002 4:13 PM Subject: Re: IBM AT power supply case/cooling question